Agathe (Isabelle Huppert) is a cold and emotionless ice queen. François (André Dussollier), Agathe’s long-term partner, has put up with her all of these years. They are not married, but they live together in a bourgeois Parisian flat with their son, Adrien (Donatien Suner). Despite their fabulous financial and social standing, their household — which is tyrannically ruled by Agathe — is a loveless one.

Agethe and François’ gravest concern is the fact that Adrien did not inherit their intellect and drive, so he is flunking out of school. Unable to test well, Adrien is destined to be sent to a trade school; which essentially means a demotion in social class — a fate worse than death for someone like Agethe. Since the school will not budge on their testing policies, Agethe and François’ sole remaining hope is Adrien’s intelligent and cultured best friend Tony (Corentin Devroey).

Tony is an extremely gifted kid who has been raised single-handedly by his crude proletariat father, Patrick (Benoît Poelvoorde). As Tony immerses himself in Adrien’s family, Patrick does his best to keep the government from taking Tony away from him. Coincidentally, Agethe and François are in dire need of a contractor to complete a remodeling project and Patrick is a contractor in desperate need of work.

Writer-director Anne Fontaine’s My Worst Nightmare begins with a trio of classically stereotyped caricatures, but as the film progresses, so do the psychological complexities of Agethe, François and Patrick. They begin to do things we would not expect of the three characters we met at the onset of the film; their inherent class distinctions become blurred. More importantly, they no longer view each other as mere cultural stereotypes; Agethe, François and Patrick begin to listen to — and therefore influence — each other. In other words, My Worst Nightmare is a whip-smart take on the age-old saying, don’t judge a book by its cover.